220706521 has 8 divisors (see below), whose sum is σ = 255691904. Its totient is φ = 186585120.

The previous prime is 220706503. The next prime is 220706531. The reversal of 220706521 is 125607022.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 220706521 - 2⁹ = 220706009 is a prime.

It is a super-2 number, since 2×220706521² = 97422736823846882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (220706531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 215445 + ... + 216466.

It is an arithmetic number, because the mean of its divisors is an integer number (31961488).

Almost surely, 2^220706521 is an apocalyptic number.

It is an amenable number.

220706521 is a deficient number, since it is larger than the sum of its proper divisors (34985383).

220706521 is an equidigital number, since it uses as much as digits as its factorization.

220706521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431991.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 220706521 is about 14856.1947012012. The cubic root of 220706521 is about 604.3266154858.

The spelling of 220706521 in words is "two hundred twenty million, seven hundred six thousand, five hundred twenty-one".